Grate the potatoes and 1 onion very finely with a grater. Then add the egg, minced meat and spices. Shape the meatballs and fry on both sides. Preheat the oven to 175 ° C.
Take the meatballs out of the pan and place in an ovenproof dish. Pour on with a little water. Cut the other onion into fine rings and place on top. Put a lid on top and cook in the oven for a good 45-60 minutes.